205780879 has 2 divisors, whose sum is σ = 205780880. Its totient is φ = 205780878.

The previous prime is 205780847. The next prime is 205780889. The reversal of 205780879 is 978087502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205780879 - 2⁵ = 205780847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205780819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102890439 + 102890440.

It is an arithmetic number, because the mean of its divisors is an integer number (102890440).

Almost surely, 2^205780879 is an apocalyptic number.

205780879 is a deficient number, since it is larger than the sum of its proper divisors (1).

205780879 is an equidigital number, since it uses as much as digits as its factorization.

205780879 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 46.

The square root of 205780879 is about 14345.0646216739. The cubic root of 205780879 is about 590.3845802515.

The spelling of 205780879 in words is "two hundred five million, seven hundred eighty thousand, eight hundred seventy-nine".